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                    1.1：移动开发技术简介
            
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                    1.2：初识Flutter
            
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                    2.1：计数器示例
            
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                    2.5：调试Flutter APP
            
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                    2.6：Dart线程模型及异常捕获
            
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                    第三章：基础组件
            
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                    3.1：Widget简介
            
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                    3.2：状态管理
            
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                    3.3：文本、字体样式
            
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                    3.4：按钮
            
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                    3.6：单选框和复选框
            
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                    3.7：输入框和表单
            
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                    第四章：布局类组件
            
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                    4.1：布局类组件简介
            
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                    4.2：线性布局（Row、Column）
            
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                    4.3：弹性布局（Flex）
            
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                    4.4：流式布局（Wrap、Flow）
            
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                    4.5：层叠布局（Stack、Positioned）
            
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                    4.6：对齐与相对定位（Align）
            
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                    第五章：容器类组件
            
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                    5.1：填充（Padding）
            
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                    5.2：尺寸限制类容器（ConstrainedBox等）
            
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                    5.3：装饰容器（DecoratedBox）
            
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                    5.4：变换（Transform）
            
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                    5.5：Container容器
            
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                    5.6：Scaffold、TabBar、底部导航
            
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                    5.7：剪裁（Clip）
            
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                    第六章：可滚动组件
            
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                    6.1：可滚动组件简介
            
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                    6.2：SingleChildScrollView
            
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                    6.3：ListView
            
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                    6.4：GridView
            
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                    6.5：CustomScrollView
            
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                    6.6：滚动监听及控制（ScrollController）
            
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                    第七章：功能型组件
            
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                    7.1：导航返回拦截（WillPopScope）
            
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                    7.2：数据共享（InheritedWidget）
            
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                    7.3： 跨组件状态共享（Provider）
            
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                    7.4：颜色和主题（Theme）
            
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                    7.5：异步UI更新（FutureBuilder、StreamBuilder）
            
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                    7.6：对话框详解
            
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        <li class="header">进阶篇</li>
        
        
    
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                    第八章：事件处理与通知
            
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        <li class="chapter " data-level="3.1.1" data-path="../chapter8/listener.html">
            
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                    8.1：原始指针事件处理
            
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        <li class="chapter " data-level="3.1.2" data-path="../chapter8/gesture.html">
            
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                    8.2：手势识别
            
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        <li class="chapter " data-level="3.1.3" data-path="../chapter8/eventbus.html">
            
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                    8.3：全局事件总线
            
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        <li class="chapter " data-level="3.1.4" data-path="../chapter8/notification.html">
            
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                    8.4：通知(Notification)
            
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        <li class="chapter " data-level="3.2" data-path="../chapter9/">
            
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                    第九章：动画
            
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        <li class="chapter " data-level="3.2.1" data-path="../chapter9/intro.html">
            
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                    9.1：Flutter动画简介
            
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                    9.2：动画结构
            
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                    9.3：自定义路由过渡动画
            
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                    9.4：Hero动画
            
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                    9.5：交织动画
            
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                    9.6：通用“动画切换”组件（AnimatedSwitcher）
            
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                    9.7：动画过渡组件
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.3" data-path="../chapter10/">
            
                <a href="../chapter10/">
            
                    
                    第十章：自定义组件
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.3.1" data-path="../chapter10/intro.html">
            
                <a href="../chapter10/intro.html">
            
                    
                    10.1：自定义组件方法简介
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.3.2" data-path="../chapter10/combine.html">
            
                <a href="../chapter10/combine.html">
            
                    
                    10.2：组合现有组件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.3.3" data-path="../chapter10/turn_box.html">
            
                <a href="../chapter10/turn_box.html">
            
                    
                    10.3：组合实例：TurnBox
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.3.4" data-path="../chapter10/custom_paint.html">
            
                <a href="../chapter10/custom_paint.html">
            
                    
                    10.4：自绘组件（CustomPaint与Canvas）
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.3.5" data-path="../chapter10/gradient_circular_progress_demo.html">
            
                <a href="../chapter10/gradient_circular_progress_demo.html">
            
                    
                    10.5：自绘实例：圆形渐变进度条(自绘)
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.4" data-path="../chapter11/">
            
                <a href="../chapter11/">
            
                    
                    第十一章：文件操作与网络请求
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.4.1" data-path="../chapter11/file_operation.html">
            
                <a href="../chapter11/file_operation.html">
            
                    
                    11.1：文件操作
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.2" data-path="../chapter11/http.html">
            
                <a href="../chapter11/http.html">
            
                    
                    11.2：Http请求-HttpClient
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.3" data-path="../chapter11/dio.html">
            
                <a href="../chapter11/dio.html">
            
                    
                    11.3：Http请求-Dio package
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.4" data-path="../chapter11/download_with_chunks.html">
            
                <a href="../chapter11/download_with_chunks.html">
            
                    
                    11.4：实例：Http分块下载
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.5" data-path="../chapter11/websocket.html">
            
                <a href="../chapter11/websocket.html">
            
                    
                    11.5：WebSocket
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.6" data-path="../chapter11/socket.html">
            
                <a href="../chapter11/socket.html">
            
                    
                    11.6：使用Socket API
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.4.7" data-path="../chapter11/json_model.html">
            
                <a href="../chapter11/json_model.html">
            
                    
                    11.7：Json转Dart Model类
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.5" data-path="../chapter12/">
            
                <a href="../chapter12/">
            
                    
                    第十二章：包与插件
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.5.1" data-path="../chapter12/develop_package.html">
            
                <a href="../chapter12/develop_package.html">
            
                    
                    12.1：开发package
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.5.2" data-path="../chapter12/platform-channel.html">
            
                <a href="../chapter12/platform-channel.html">
            
                    
                    12.2：平台通道简介
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.5.3" data-path="../chapter12/develop_plugin.html">
            
                <a href="../chapter12/develop_plugin.html">
            
                    
                    12.3：开发Flutter插件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.5.4" data-path="../chapter12/android_implement.html">
            
                <a href="../chapter12/android_implement.html">
            
                    
                    12.4：插件开发：实现Android端API
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.5.5" data-path="../chapter12/ios_implement.html">
            
                <a href="../chapter12/ios_implement.html">
            
                    
                    12.5：插件开发：实现IOS端API
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.5.6" data-path="../chapter12/texture_platformview.html">
            
                <a href="../chapter12/texture_platformview.html">
            
                    
                    12.6：Texture和PlatformView
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.6" data-path="../chapter13/">
            
                <a href="../chapter13/">
            
                    
                    第十三章：国际化
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.6.1" data-path="../chapter13/multi_languages_support.html">
            
                <a href="../chapter13/multi_languages_support.html">
            
                    
                    13.1：让App支持多语言
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.6.2" data-path="../chapter13/locallization_implement.html">
            
                <a href="../chapter13/locallization_implement.html">
            
                    
                    13.2：实现Localizations
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.6.3" data-path="../chapter13/intl.html">
            
                <a href="../chapter13/intl.html">
            
                    
                    13.3：使用Intl包
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.6.4" data-path="../chapter13/faq.html">
            
                <a href="../chapter13/faq.html">
            
                    
                    13.4：国际化常见问题
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="3.7" data-path="../chapter14/">
            
                <a href="../chapter14/">
            
                    
                    第十四章：Flutter核心原理
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.7.1" data-path="../chapter14/flutter_ui_system.html">
            
                <a href="../chapter14/flutter_ui_system.html">
            
                    
                    14.1：Flutter UI系统
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.7.2" data-path="../chapter14/element_buildcontext.html">
            
                <a href="../chapter14/element_buildcontext.html">
            
                    
                    14.2：Element和BuildContext
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.7.3" data-path="../chapter14/render_object.html">
            
                <a href="../chapter14/render_object.html">
            
                    
                    14.3：RenderObject与RenderBox
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.7.4" data-path="../chapter14/flutter_app_startup.html">
            
                <a href="../chapter14/flutter_app_startup.html">
            
                    
                    14.4：Flutter从启动到显示
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.7.5" data-path="../chapter14/image_and_cache.html">
            
                <a href="../chapter14/image_and_cache.html">
            
                    
                    14.5：Flutter图片加载与缓存
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">实例篇</li>
        
        
    
        <li class="chapter " data-level="4.1" data-path="intro.html">
            
                <a href="intro.html">
            
                    
                    第十五章：一个完整的Flutter应用
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="4.1.1" data-path="intro.html">
            
                <a href="intro.html">
            
                    
                    15.1：应用简介
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.2" data-path="code_structure.html">
            
                <a href="code_structure.html">
            
                    
                    15.2：APP代码结构
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.3" data-path="models.html">
            
                <a href="models.html">
            
                    
                    15.3：Model类定义
            
                </a>
            

            
        </li>
    
        <li class="chapter active" data-level="4.1.4" data-path="globals.html">
            
                <a href="globals.html">
            
                    
                    15.4：全局变量及共享状态
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.5" data-path="network.html">
            
                <a href="network.html">
            
                    
                    15.5：网络请求封装
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.6" data-path="entry.html">
            
                <a href="entry.html">
            
                    
                    15.6：App入口及首页
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.7" data-path="login_page.html">
            
                <a href="login_page.html">
            
                    
                    15.7：登录页
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.8" data-path="language_and_theme_setting.html">
            
                <a href="language_and_theme_setting.html">
            
                    
                    15.8：多语言和多主题
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    

    <li class="divider"></li>

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        <a href="https://www.gitbook.com" target="blank" class="https://pcdn.flutterchina.club/gitbook-link">
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                                <h1 id="154-&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x53CA;&#x5171;&#x4EAB;&#x72B6;&#x6001;">15.4 &#x5168;&#x5C40;&#x53D8;&#x91CF;&#x53CA;&#x5171;&#x4EAB;&#x72B6;&#x6001;</h1>
<p>&#x5E94;&#x7528;&#x7A0B;&#x5E8F;&#x4E2D;&#x901A;&#x5E38;&#x4F1A;&#x5305;&#x542B;&#x4E00;&#x4E9B;&#x8D2F;&#x7A7F;APP&#x751F;&#x547D;&#x5468;&#x671F;&#x7684;&#x53D8;&#x91CF;&#x4FE1;&#x606F;&#xFF0C;&#x8FD9;&#x4E9B;&#x4FE1;&#x606F;&#x5728;APP&#x5927;&#x591A;&#x6570;&#x5730;&#x65B9;&#x53EF;&#x80FD;&#x90FD;&#x4F1A;&#x88AB;&#x7528;&#x5230;&#xFF0C;&#x6BD4;&#x5982;&#x5F53;&#x524D;&#x7528;&#x6237;&#x4FE1;&#x606F;&#x3001;Local&#x4FE1;&#x606F;&#x7B49;&#x3002;&#x5728;Flutter&#x4E2D;&#x6211;&#x4EEC;&#x628A;&#x9700;&#x8981;&#x5168;&#x5C40;&#x5171;&#x4EAB;&#x7684;&#x4FE1;&#x606F;&#x5206;&#x4E3A;&#x4E24;&#x7C7B;&#xFF1A;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x548C;&#x5171;&#x4EAB;&#x72B6;&#x6001;&#x3002;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x5C31;&#x662F;&#x5355;&#x7EAF;&#x6307;&#x4F1A;&#x8D2F;&#x7A7F;&#x6574;&#x4E2A;APP&#x751F;&#x547D;&#x5468;&#x671F;&#x7684;&#x53D8;&#x91CF;&#xFF0C;&#x7528;&#x4E8E;&#x5355;&#x7EAF;&#x7684;&#x4FDD;&#x5B58;&#x4E00;&#x4E9B;&#x4FE1;&#x606F;&#xFF0C;&#x6216;&#x8005;&#x5C01;&#x88C5;&#x4E00;&#x4E9B;&#x5168;&#x5C40;&#x5DE5;&#x5177;&#x548C;&#x65B9;&#x6CD5;&#x7684;&#x5BF9;&#x8C61;&#x3002;&#x800C;&#x5171;&#x4EAB;&#x72B6;&#x6001;&#x5219;&#x662F;&#x6307;&#x54EA;&#x4E9B;&#x9700;&#x8981;&#x8DE8;&#x7EC4;&#x4EF6;&#x6216;&#x8DE8;&#x8DEF;&#x7531;&#x5171;&#x4EAB;&#x7684;&#x4FE1;&#x606F;&#xFF0C;&#x8FD9;&#x4E9B;&#x4FE1;&#x606F;&#x901A;&#x5E38;&#x4E5F;&#x662F;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#xFF0C;&#x800C;&#x5171;&#x4EAB;&#x72B6;&#x6001;&#x548C;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x7684;&#x4E0D;&#x540C;&#x5728;&#x4E8E;&#x524D;&#x8005;&#x53D1;&#x751F;&#x6539;&#x53D8;&#x65F6;&#x9700;&#x8981;&#x901A;&#x77E5;&#x6240;&#x6709;&#x4F7F;&#x7528;&#x8BE5;&#x72B6;&#x6001;&#x7684;&#x7EC4;&#x4EF6;&#xFF0C;&#x800C;&#x540E;&#x8005;&#x4E0D;&#x9700;&#x8981;&#x3002;&#x4E3A;&#x6B64;&#xFF0C;&#x6211;&#x4EEC;&#x5C06;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x548C;&#x5171;&#x4EAB;&#x72B6;&#x6001;&#x5206;&#x5F00;&#x5355;&#x72EC;&#x7BA1;&#x7406;&#x3002;</p>
<h2 id="1541-&#x5168;&#x5C40;&#x53D8;&#x91CF;-global&#x7C7B;">15.4.1 &#x5168;&#x5C40;&#x53D8;&#x91CF;-Global&#x7C7B;</h2>
<p>&#x6211;&#x4EEC;&#x5728;&#x201C;lib/common&#x201D;&#x76EE;&#x5F55;&#x4E0B;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;<code>Global</code>&#x7C7B;&#xFF0C;&#x5B83;&#x4E3B;&#x8981;&#x7BA1;&#x7406;APP&#x7684;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#xFF0C;&#x5B9A;&#x4E49;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token comment">// &#x63D0;&#x4F9B;&#x4E94;&#x5957;&#x53EF;&#x9009;&#x4E3B;&#x9898;&#x8272;</span>
<span class="token keyword">const</span> _themes <span class="token operator">=</span> <span class="token operator">&lt;</span>MaterialColor<span class="token operator">&gt;</span><span class="token punctuation">[</span>
  Colors<span class="token punctuation">.</span>blue<span class="token punctuation">,</span>
  Colors<span class="token punctuation">.</span>cyan<span class="token punctuation">,</span>
  Colors<span class="token punctuation">.</span>teal<span class="token punctuation">,</span>
  Colors<span class="token punctuation">.</span>green<span class="token punctuation">,</span>
  Colors<span class="token punctuation">.</span>red<span class="token punctuation">,</span>
<span class="token punctuation">]</span><span class="token punctuation">;</span>

<span class="token keyword">class</span> <span class="token class-name">Global</span> <span class="token punctuation">{</span>
  <span class="token keyword">static</span> SharedPreferences _prefs<span class="token punctuation">;</span>
  <span class="token keyword">static</span> Profile profile <span class="token operator">=</span> <span class="token function">Profile</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token comment">// &#x7F51;&#x7EDC;&#x7F13;&#x5B58;&#x5BF9;&#x8C61;</span>
  <span class="token keyword">static</span> NetCache netCache <span class="token operator">=</span> <span class="token function">NetCache</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

  <span class="token comment">// &#x53EF;&#x9009;&#x7684;&#x4E3B;&#x9898;&#x5217;&#x8868;</span>
  <span class="token keyword">static</span> List<span class="token operator">&lt;</span>MaterialColor<span class="token operator">&gt;</span> <span class="token keyword">get</span> themes <span class="token operator">=</span><span class="token operator">&gt;</span> _themes<span class="token punctuation">;</span>

  <span class="token comment">// &#x662F;&#x5426;&#x4E3A;release&#x7248;</span>
  <span class="token keyword">static</span> bool <span class="token keyword">get</span> isRelease <span class="token operator">=</span><span class="token operator">&gt;</span> bool<span class="token punctuation">.</span><span class="token function">fromEnvironment</span><span class="token punctuation">(</span><span class="token string">&quot;dart.vm.product&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

  <span class="token comment">//&#x521D;&#x59CB;&#x5316;&#x5168;&#x5C40;&#x4FE1;&#x606F;&#xFF0C;&#x4F1A;&#x5728;APP&#x542F;&#x52A8;&#x65F6;&#x6267;&#x884C;</span>
  <span class="token keyword">static</span> Future <span class="token function">init</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token keyword">async</span> <span class="token punctuation">{</span>
    _prefs <span class="token operator">=</span> <span class="token keyword">await</span> SharedPreferences<span class="token punctuation">.</span><span class="token function">getInstance</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token keyword">var</span> _profile <span class="token operator">=</span> _prefs<span class="token punctuation">.</span><span class="token function">getString</span><span class="token punctuation">(</span><span class="token string">&quot;profile&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>_profile <span class="token operator">!=</span> <span class="token keyword">null</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">try</span> <span class="token punctuation">{</span>
        profile <span class="token operator">=</span> Profile<span class="token punctuation">.</span><span class="token function">fromJson</span><span class="token punctuation">(</span><span class="token function">jsonDecode</span><span class="token punctuation">(</span>_profile<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
      <span class="token punctuation">}</span> <span class="token keyword">catch</span> <span class="token punctuation">(</span>e<span class="token punctuation">)</span> <span class="token punctuation">{</span>
        <span class="token function">print</span><span class="token punctuation">(</span>e<span class="token punctuation">)</span><span class="token punctuation">;</span>
      <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>

    <span class="token comment">// &#x5982;&#x679C;&#x6CA1;&#x6709;&#x7F13;&#x5B58;&#x7B56;&#x7565;&#xFF0C;&#x8BBE;&#x7F6E;&#x9ED8;&#x8BA4;&#x7F13;&#x5B58;&#x7B56;&#x7565;</span>
    profile<span class="token punctuation">.</span>cache <span class="token operator">=</span> profile<span class="token punctuation">.</span>cache <span class="token operator">?</span><span class="token operator">?</span> <span class="token function">CacheConfig</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
      <span class="token punctuation">.</span><span class="token punctuation">.</span>enable <span class="token operator">=</span> <span class="token boolean">true</span>
      <span class="token punctuation">.</span><span class="token punctuation">.</span>maxAge <span class="token operator">=</span> <span class="token number">3600</span>
      <span class="token punctuation">.</span><span class="token punctuation">.</span>maxCount <span class="token operator">=</span> <span class="token number">100</span><span class="token punctuation">;</span>

    <span class="token comment">//&#x521D;&#x59CB;&#x5316;&#x7F51;&#x7EDC;&#x8BF7;&#x6C42;&#x76F8;&#x5173;&#x914D;&#x7F6E;</span>
    Git<span class="token punctuation">.</span><span class="token function">init</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>

  <span class="token comment">// &#x6301;&#x4E45;&#x5316;Profile&#x4FE1;&#x606F;</span>
  <span class="token keyword">static</span> <span class="token function">saveProfile</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span>
      _prefs<span class="token punctuation">.</span><span class="token function">setString</span><span class="token punctuation">(</span><span class="token string">&quot;profile&quot;</span><span class="token punctuation">,</span> <span class="token function">jsonEncode</span><span class="token punctuation">(</span>profile<span class="token punctuation">.</span><span class="token function">toJson</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre>
<p>Global&#x7C7B;&#x7684;&#x5404;&#x4E2A;&#x5B57;&#x6BB5;&#x7684;&#x610F;&#x4E49;&#x90FD;&#x6709;&#x6CE8;&#x91CA;&#xFF0C;&#x5728;&#x6B64;&#x4E0D;&#x518D;&#x8D58;&#x8FF0;&#xFF0C;&#x9700;&#x8981;&#x6CE8;&#x610F;&#x7684;&#x662F;<code>init()</code>&#x9700;&#x8981;&#x5728;App&#x542F;&#x52A8;&#x65F6;&#x5C31;&#x8981;&#x6267;&#x884C;&#xFF0C;&#x6240;&#x4EE5;&#x5E94;&#x7528;&#x7684;<code>main</code>&#x65B9;&#x6CD5;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span> Global<span class="token punctuation">.</span><span class="token function">init</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">then</span><span class="token punctuation">(</span><span class="token punctuation">(</span>e<span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span> <span class="token function">runApp</span><span class="token punctuation">(</span><span class="token function">MyApp</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre>
<p>&#x5728;&#x6B64;&#xFF0C;&#x4E00;&#x5B9A;&#x8981;&#x786E;&#x4FDD;<code>Global.init()</code>&#x65B9;&#x6CD5;&#x4E0D;&#x80FD;&#x629B;&#x51FA;&#x5F02;&#x5E38;&#xFF0C;&#x5426;&#x5219; <code>runApp(MyApp())</code>&#x6839;&#x672C;&#x6267;&#x884C;&#x4E0D;&#x5230;&#x3002;</p>
<h2 id="1542-&#x5171;&#x4EAB;&#x72B6;&#x6001;">15.4.2 &#x5171;&#x4EAB;&#x72B6;&#x6001;</h2>
<p>&#x6709;&#x4E86;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#xFF0C;&#x6211;&#x4EEC;&#x8FD8;&#x9700;&#x8981;&#x8003;&#x8651;&#x5982;&#x4F55;&#x8DE8;&#x7EC4;&#x4EF6;&#x5171;&#x4EAB;&#x72B6;&#x6001;&#x3002;&#x5F53;&#x7136;&#xFF0C;&#x5982;&#x679C;&#x6211;&#x4EEC;&#x5C06;&#x8981;&#x5171;&#x4EAB;&#x7684;&#x72B6;&#x6001;&#x5168;&#x90E8;&#x7528;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#x66FF;&#x4EE3;&#x4E5F;&#x662F;&#x53EF;&#x4EE5;&#x7684;&#xFF0C;&#x4F46;&#x662F;&#x8FD9;&#x5728;Flutter&#x5F00;&#x53D1;&#x4E2D;&#x5E76;&#x4E0D;&#x662F;&#x4E00;&#x4E2A;&#x597D;&#x4E3B;&#x610F;&#xFF0C;&#x56E0;&#x4E3A;&#x7EC4;&#x4EF6;&#x7684;&#x72B6;&#x6001;&#x662F;&#x548C;UI&#x76F8;&#x5173;&#xFF0C;&#x800C;&#x5728;&#x72B6;&#x6001;&#x6539;&#x53D8;&#x65F6;&#x6211;&#x4EEC;&#x4F1A;&#x671F;&#x671B;&#x4F9D;&#x8D56;&#x8BE5;&#x72B6;&#x6001;&#x7684;UI&#x7EC4;&#x4EF6;&#x4F1A;&#x81EA;&#x52A8;&#x66F4;&#x65B0;&#xFF0C;&#x5982;&#x679C;&#x4F7F;&#x7528;&#x5168;&#x5C40;&#x53D8;&#x91CF;&#xFF0C;&#x90A3;&#x4E48;&#x6211;&#x4EEC;&#x5FC5;&#x987B;&#x5F97;&#x53BB;&#x624B;&#x52A8;&#x5904;&#x7406;&#x72B6;&#x6001;&#x53D8;&#x52A8;&#x901A;&#x77E5;&#x3001;&#x63A5;&#x6536;&#x673A;&#x5236;&#x4EE5;&#x53CA;&#x53D8;&#x91CF;&#x548C;&#x7EC4;&#x4EF6;&#x4F9D;&#x8D56;&#x5173;&#x7CFB;&#x3002;&#x56E0;&#x6B64;&#xFF0C;&#x672C;&#x5B9E;&#x4F8B;&#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x4F7F;&#x7528;&#x524D;&#x9762;&#x4ECB;&#x7ECD;&#x8FC7;&#x7684;Provider&#x5305;&#x6765;&#x5B9E;&#x73B0;&#x8DE8;&#x7EC4;&#x4EF6;&#x72B6;&#x6001;&#x5171;&#x4EAB;&#xFF0C;&#x56E0;&#x6B64;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x5B9A;&#x4E49;&#x76F8;&#x5173;&#x7684;Provider&#x3002;&#x5728;&#x672C;&#x5B9E;&#x4F8B;&#x4E2D;&#xFF0C;&#x9700;&#x8981;&#x5171;&#x4EAB;&#x7684;&#x72B6;&#x6001;&#x6709;&#x767B;&#x5F55;&#x7528;&#x6237;&#x4FE1;&#x606F;&#x3001;APP&#x4E3B;&#x9898;&#x4FE1;&#x606F;&#x3001;APP&#x8BED;&#x8A00;&#x4FE1;&#x606F;&#x3002;&#x7531;&#x4E8E;&#x8FD9;&#x4E9B;&#x4FE1;&#x606F;&#x6539;&#x53D8;&#x540E;&#x90FD;&#x8981;&#x7ACB;&#x5373;&#x901A;&#x77E5;&#x5176;&#x5B83;&#x4F9D;&#x8D56;&#x7684;&#x8BE5;&#x4FE1;&#x606F;&#x7684;Widget&#x66F4;&#x65B0;&#xFF0C;&#x6240;&#x4EE5;&#x6211;&#x4EEC;&#x5E94;&#x8BE5;&#x4F7F;&#x7528;<code>ChangeNotifierProvider</code>&#xFF0C;&#x53E6;&#x5916;&#xFF0C;&#x8FD9;&#x4E9B;&#x4FE1;&#x606F;&#x6539;&#x53D8;&#x540E;&#x90FD;&#x662F;&#x9700;&#x8981;&#x66F4;&#x65B0;Profile&#x4FE1;&#x606F;&#x5E76;&#x8FDB;&#x884C;&#x6301;&#x4E45;&#x5316;&#x7684;&#x3002;&#x7EFC;&#x4E0A;&#x6240;&#x8FF0;&#xFF0C;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x5B9A;&#x4E49;&#x4E00;&#x4E2A;<code>ProfileChangeNotifier</code>&#x57FA;&#x7C7B;&#xFF0C;&#x7136;&#x540E;&#x8BA9;&#x9700;&#x8981;&#x5171;&#x4EAB;&#x7684;Model&#x7EE7;&#x627F;&#x81EA;&#x8BE5;&#x7C7B;&#x5373;&#x53EF;&#xFF0C;<code>ProfileChangeNotifier</code>&#x5B9A;&#x4E49;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token keyword">class</span> <span class="token class-name">ProfileChangeNotifier</span> <span class="token keyword">extends</span> <span class="token class-name">ChangeNotifier</span> <span class="token punctuation">{</span>
  Profile <span class="token keyword">get</span> _profile <span class="token operator">=</span><span class="token operator">&gt;</span> Global<span class="token punctuation">.</span>profile<span class="token punctuation">;</span>

  <span class="token metadata symbol">@override</span>
  <span class="token keyword">void</span> <span class="token function">notifyListeners</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    Global<span class="token punctuation">.</span><span class="token function">saveProfile</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">//&#x4FDD;&#x5B58;Profile&#x53D8;&#x66F4;</span>
    <span class="token keyword">super</span><span class="token punctuation">.</span><span class="token function">notifyListeners</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">//&#x901A;&#x77E5;&#x4F9D;&#x8D56;&#x7684;Widget&#x66F4;&#x65B0;</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>
<h3 id="&#x7528;&#x6237;&#x72B6;&#x6001;">&#x7528;&#x6237;&#x72B6;&#x6001;</h3>
<p>&#x7528;&#x6237;&#x72B6;&#x6001;&#x5728;&#x767B;&#x5F55;&#x72B6;&#x6001;&#x53D1;&#x751F;&#x53D8;&#x5316;&#x65F6;&#x66F4;&#x65B0;&#x3001;&#x901A;&#x77E5;&#x5176;&#x4F9D;&#x8D56;&#x9879;&#xFF0C;&#x6211;&#x4EEC;&#x5B9A;&#x4E49;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token keyword">class</span> <span class="token class-name">UserModel</span> <span class="token keyword">extends</span> <span class="token class-name">ProfileChangeNotifier</span> <span class="token punctuation">{</span>
  User <span class="token keyword">get</span> user <span class="token operator">=</span><span class="token operator">&gt;</span> _profile<span class="token punctuation">.</span>user<span class="token punctuation">;</span>

  <span class="token comment">// APP&#x662F;&#x5426;&#x767B;&#x5F55;(&#x5982;&#x679C;&#x6709;&#x7528;&#x6237;&#x4FE1;&#x606F;&#xFF0C;&#x5219;&#x8BC1;&#x660E;&#x767B;&#x5F55;&#x8FC7;)</span>
  bool <span class="token keyword">get</span> isLogin <span class="token operator">=</span><span class="token operator">&gt;</span> user <span class="token operator">!=</span> <span class="token keyword">null</span><span class="token punctuation">;</span>

  <span class="token comment">//&#x7528;&#x6237;&#x4FE1;&#x606F;&#x53D1;&#x751F;&#x53D8;&#x5316;&#xFF0C;&#x66F4;&#x65B0;&#x7528;&#x6237;&#x4FE1;&#x606F;&#x5E76;&#x901A;&#x77E5;&#x4F9D;&#x8D56;&#x5B83;&#x7684;&#x5B50;&#x5B59;Widgets&#x66F4;&#x65B0;</span>
  <span class="token keyword">set</span> <span class="token function">user</span><span class="token punctuation">(</span>User user<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>user<span class="token operator">?</span><span class="token punctuation">.</span>login <span class="token operator">!=</span> _profile<span class="token punctuation">.</span>user<span class="token operator">?</span><span class="token punctuation">.</span>login<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      _profile<span class="token punctuation">.</span>lastLogin <span class="token operator">=</span> _profile<span class="token punctuation">.</span>user<span class="token operator">?</span><span class="token punctuation">.</span>login<span class="token punctuation">;</span>
      _profile<span class="token punctuation">.</span>user <span class="token operator">=</span> user<span class="token punctuation">;</span>
      <span class="token function">notifyListeners</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>
<h3 id="app&#x4E3B;&#x9898;&#x72B6;&#x6001;">APP&#x4E3B;&#x9898;&#x72B6;&#x6001;</h3>
<p>&#x4E3B;&#x9898;&#x72B6;&#x6001;&#x5728;&#x7528;&#x6237;&#x66F4;&#x6362;APP&#x4E3B;&#x9898;&#x65F6;&#x66F4;&#x65B0;&#x3001;&#x901A;&#x77E5;&#x5176;&#x4F9D;&#x8D56;&#x9879;&#xFF0C;&#x5B9A;&#x4E49;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token keyword">class</span> <span class="token class-name">ThemeModel</span> <span class="token keyword">extends</span> <span class="token class-name">ProfileChangeNotifier</span> <span class="token punctuation">{</span>
  <span class="token comment">// &#x83B7;&#x53D6;&#x5F53;&#x524D;&#x4E3B;&#x9898;&#xFF0C;&#x5982;&#x679C;&#x4E3A;&#x8BBE;&#x7F6E;&#x4E3B;&#x9898;&#xFF0C;&#x5219;&#x9ED8;&#x8BA4;&#x4F7F;&#x7528;&#x84DD;&#x8272;&#x4E3B;&#x9898;</span>
  ColorSwatch <span class="token keyword">get</span> theme <span class="token operator">=</span><span class="token operator">&gt;</span> Global<span class="token punctuation">.</span>themes
      <span class="token punctuation">.</span><span class="token function">firstWhere</span><span class="token punctuation">(</span><span class="token punctuation">(</span>e<span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span> e<span class="token punctuation">.</span>value <span class="token operator">==</span> _profile<span class="token punctuation">.</span>theme<span class="token punctuation">,</span> orElse<span class="token punctuation">:</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=</span><span class="token operator">&gt;</span> Colors<span class="token punctuation">.</span>blue<span class="token punctuation">)</span><span class="token punctuation">;</span>

  <span class="token comment">// &#x4E3B;&#x9898;&#x6539;&#x53D8;&#x540E;&#xFF0C;&#x901A;&#x77E5;&#x5176;&#x4F9D;&#x8D56;&#x9879;&#xFF0C;&#x65B0;&#x4E3B;&#x9898;&#x4F1A;&#x7ACB;&#x5373;&#x751F;&#x6548;</span>
  <span class="token keyword">set</span> <span class="token function">theme</span><span class="token punctuation">(</span>ColorSwatch color<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>color <span class="token operator">!=</span> theme<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      _profile<span class="token punctuation">.</span>theme <span class="token operator">=</span> color<span class="token punctuation">[</span><span class="token number">500</span><span class="token punctuation">]</span><span class="token punctuation">.</span>value<span class="token punctuation">;</span>
      <span class="token function">notifyListeners</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>
<h3 id="app&#x8BED;&#x8A00;&#x72B6;&#x6001;">APP&#x8BED;&#x8A00;&#x72B6;&#x6001;</h3>
<p>&#x5F53;APP&#x8BED;&#x8A00;&#x9009;&#x4E3A;&#x8DDF;&#x968F;&#x7CFB;&#x7EDF;&#xFF08;Auto&#xFF09;&#x65F6;&#xFF0C;&#x5728;&#x7CFB;&#x901A;&#x8BED;&#x8A00;&#x6539;&#x53D8;&#x65F6;&#xFF0C;APP&#x8BED;&#x8A00;&#x4F1A;&#x66F4;&#x65B0;&#xFF1B;&#x5F53;&#x7528;&#x6237;&#x5728;APP&#x4E2D;&#x9009;&#x5B9A;&#x4E86;&#x5177;&#x4F53;&#x8BED;&#x8A00;&#x65F6;&#xFF08;&#x7F8E;&#x56FD;&#x82F1;&#x8BED;&#x6216;&#x4E2D;&#x6587;&#x7B80;&#x4F53;&#xFF09;&#xFF0C;&#x5219;APP&#x4FBF;&#x4F1A;&#x4E00;&#x76F4;&#x4F7F;&#x7528;&#x7528;&#x6237;&#x9009;&#x5B9A;&#x7684;&#x8BED;&#x8A00;&#xFF0C;&#x4E0D;&#x4F1A;&#x518D;&#x968F;&#x7CFB;&#x7EDF;&#x8BED;&#x8A00;&#x800C;&#x53D8;&#x3002;&#x8BED;&#x8A00;&#x72B6;&#x6001;&#x7C7B;&#x5B9A;&#x4E49;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code class="lang-dart"><span class="token keyword">class</span> <span class="token class-name">LocaleModel</span> <span class="token keyword">extends</span> <span class="token class-name">ProfileChangeNotifier</span> <span class="token punctuation">{</span>
  <span class="token comment">// &#x83B7;&#x53D6;&#x5F53;&#x524D;&#x7528;&#x6237;&#x7684;APP&#x8BED;&#x8A00;&#x914D;&#x7F6E;Locale&#x7C7B;&#xFF0C;&#x5982;&#x679C;&#x4E3A;null&#xFF0C;&#x5219;&#x8BED;&#x8A00;&#x8DDF;&#x968F;&#x7CFB;&#x7EDF;&#x8BED;&#x8A00;</span>
  Locale <span class="token function">getLocale</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>_profile<span class="token punctuation">.</span>locale <span class="token operator">==</span> <span class="token keyword">null</span><span class="token punctuation">)</span> <span class="token keyword">return</span> <span class="token keyword">null</span><span class="token punctuation">;</span>
    <span class="token keyword">var</span> t <span class="token operator">=</span> _profile<span class="token punctuation">.</span>locale<span class="token punctuation">.</span><span class="token function">split</span><span class="token punctuation">(</span><span class="token string">&quot;_&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token keyword">return</span> <span class="token function">Locale</span><span class="token punctuation">(</span>t<span class="token punctuation">[</span><span class="token number">0</span><span class="token punctuation">]</span><span class="token punctuation">,</span> t<span class="token punctuation">[</span><span class="token number">1</span><span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>

  <span class="token comment">// &#x83B7;&#x53D6;&#x5F53;&#x524D;Locale&#x7684;&#x5B57;&#x7B26;&#x4E32;&#x8868;&#x793A;</span>
  String <span class="token keyword">get</span> locale <span class="token operator">=</span><span class="token operator">&gt;</span> _profile<span class="token punctuation">.</span>locale<span class="token punctuation">;</span>

  <span class="token comment">// &#x7528;&#x6237;&#x6539;&#x53D8;APP&#x8BED;&#x8A00;&#x540E;&#xFF0C;&#x901A;&#x77E5;&#x4F9D;&#x8D56;&#x9879;&#x66F4;&#x65B0;&#xFF0C;&#x65B0;&#x8BED;&#x8A00;&#x4F1A;&#x7ACB;&#x5373;&#x751F;&#x6548;</span>
  <span class="token keyword">set</span> <span class="token function">locale</span><span class="token punctuation">(</span>String locale<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>locale <span class="token operator">!=</span> _profile<span class="token punctuation">.</span>locale<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      _profile<span class="token punctuation">.</span>locale <span class="token operator">=</span> locale<span class="token punctuation">;</span>
      <span class="token function">notifyListeners</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre>

                                
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